三维连续镍-铝(骨架)增强铝基复合材料的磨损行为

Wear Behavior of 3D-Network Ni-Al(Skeleton) Reinforced Aluminum Alloy Composites

采用真空吸铸和真空热处理技术制备了三维连续镍-铝(骨架)增强铝基复合材料,研究了其在干摩擦条件下的磨损行为。结果表明,复合材料的耐磨性能远优于基体合金。主要是由于硬的Ni2Al3金属间化合物(骨架)裸露在磨损表面,成为微凸体,起承载作用,抑制或延迟了基体从轻微磨损向严重磨损的转变时间。同时将载荷分散至各个方向,抑制了磨损面基体合金因塑性变形产生的流失。基体合金的磨损机制为严重粘着磨损,复合材料的磨损为以磨粒磨损为主和轻微的粘着磨损。

A 3D-network Ni-Al（skeleton） reinforced aluminum alloy composites were designed and fabricated by vacuum suction casting combining vacuum heat treatment.The dry sliding wear behaviors of the composites prepared under various loads were examined.The results show that the wear resistance of composites is far superior to that of matrix alloys.It is supposed the network Ni2Al3（skeleton） intermetallic compound can be subjected to the load applied on the sliding surface as concave particles to restrain or delay the transformation of aluminum alloy from the mild wear to the severe wear.Meanwhile,it can uniformly transfer the load on the surface,inhibiting the loss of the aluminum alloy on wear surface from plastic deformation.The wear mechanism of matrix alloy is characterized by severe adhesive wear,and wear mechanism of the composites is mainly characterized by abrasive wear with slightly adhesion wear.